Biological Properties and Absolute Configuration of Flavanones From Calceolariathyrsiflora Graham

• Main Authors: Ernesto Valdés (Author), César González (Author), Katy Díaz (Author), Yesseny Vásquez-Martínez (Author), Carolina Mascayano (Author), Claudia Torrent (Author), Francisco Cabezas (Author), Sophia Mejias (Author), Margarita Montoya (Author), Marcelo Cortez-San Martín (Author), Marcelo A. Muñoz (Author), Pedro Joseph-Nathan (Author), Mauricio Osorio (Author), Lautaro Taborga (Author)
• Format: Book
• Published: Frontiers Media S.A., 2020-07-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Flavanones (-)-(2S)-5,4'-dihydroxy-7-methoxyflavanone (1) and (-)-(2S)-5,3',4'-trihydroxy-7-methoxyflavanone (2) were isolated from the extracts of Calceolariathyrsiflora Graham, an endemic perennial small shrub growing in the central zone of Chile. The absolute configuration of these compounds was resolved by optical rotation experiments and in silico calculations. Three analogs (3, 4, and 5) were synthesized to do structure-activity relationships with the biological assays studied. Biological tests revealed that only flavanone 2 exhibited a moderate inhibitory activity against the methicillin-resistant strain S. aureus MRSA 97-77 (MIC value of 50 µg/ml). In addition, flavanone 2 showed a potent, selective, and competitive inhibition of 5-hLOX, which supports the traditional use of this plant as an anti-inflammatory in diseases of the respiratory tract. Also, 2 exhibited cytotoxic and selective effects against B16-F10 (8.07 ± 1.61 µM) but 4.6- and 17-fold lesser activity than etoposide and taxol.

Item Description

1663-9812
10.3389/fphar.2020.01125